Double-pole double-throw snap switch



July 28, 1953 w. A. MARTIN 7 DOUBLE POLE DOUBLE THROW SNAP swrrcn FiledJan/23, 1950 2 Sheets-Sheet 1 8/ 7z ma i. a; 86 4 5a M INVENTOR. 64 I i52 37 9 Mad QM i y Z! Z 2 '3 27 4L ATTYS July 28, 1953 w. A. MARTIN 2647,17

DOUBLE POLE DOUBLE THROW SNAP SWITCH Filed Jan. 23, 1950 V 2Sheets-Sheet 2 INVENTOR. 74% Q.

Patented July 28, 1953 DOUBLE-POLE DOUBLE-THROW SNAP SWITCH Wilbert A.Martin, Freeport, Ill., assignor, by mesne assignments, toMinneapolis-Honeywell Regulator Company, Minneapolis, Minn, acorporation of Delaware Application January 23, 1950, Serial No. 140,069

19 Claims. 1

This invention relates to snap acting devices and more particularly to adouble pole double throw snap acting switch.

An object of this invention is to provide a double pole double throwsnap acting switch that has the same overall and mountingdimensions as astandard precision snap acting switch.

Another object of the invention is the provision of a double pole doublethrow switch having a novel snap acting spring system that effects apositive pressure between the movable and the fixed contacts until theinstant of movement of the movable contacts between the fixed contacts,and that insures a uniform pressure between the movable contacts and thefixed contacts.

Another object of the invention is the provision of a novel snap actingspring system having a novel combination of levers for obtainingsuccessive snap movements.

Another object of the invention is the provision of a double snap actingspring system that is simple to construct, that is easy to assemble,that is positive in its action, that is rugged, that has a relativelylong service life, and that is rel- I atively inexpensive tomanufacture.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which Figure 1 is a perspective view of adouble pole double throw snap acting switch embodying the presentinvention;

Fig. 2 is an enlarged side elevational view of the switch shown inFigure 1 with portions of a side wall cut away to show details ofconstruction of the spring system;

Fig. 3 is a sectional view taken substantially along the line 3-3 ofFig. 2;

Fig. 4 is a greatly enlarged fragmentary side elevational view of theswitch similar to Fig. 2 with members of the snap acting spring systemin section and the driving member of the spring system in a position tourge the movable contacts into engagement with the lower contacts;

Fig. 5 is a sectional view taken substantially along the line 55 of Fig.3;

Fig. 6 is a view similar to Fig. 4 showing the relation of the partsprior to the first snap movement;

Fig. 7 is a view similar to Fig. 4 showing the position of the partsfollowing the first snap movement;

Fig. 8 is a view similar to Fig. 4 showing the relation of the partsafter the second snap move-'- ment;

Fig. 9 is a section-a1 view taken substantially along the line 99 ofFig. 4, and

Fig. 10 is an enlarged sectional view taken substantially along the linel0l0 of Fig. 2.

The invention is shown embodied in a double pole double throw electricswitch. In general the latter comprises a pair of mobile-contacts 2|movable between opposed positions, a double snap acting spring system.22 interconnected with the mobile contacts 2! and operable to move thelatter between opposed positions with a snap action and a plunger 23 foractuating the double snap acting spring system 22. The mobile contacts2| and the spring system 22 are disposed in a chamber 24 of a housing26. The latter may be formed from any suitable material such asinsulating material and includes a base or support 21 and a removablecover 28 interfitting with the base 21 to define the chamber 24. Theplunger '23 is of conventional construction and extends through thecover 28 for engagement with the spring system.

The mobile contacts 2| (see Fig. 2) are disposed centrally of thechamber 24 and are mounted on the free ends of spaced contact carriers29, in this embodiment of the invention, elongated flexible resilientleaf springs. The opposite end of each carrier is secured, as by weldingor the like, to one end of a support 3| (one only being shown) toprovide a cantilever mounting for carriers 29. Each support 3| rests ona shoulder 32 formed near one end of the chamber 24. The opposite end ofthe support 3| is offset with respect to the end supporting the carrier29 and is secured to the base 21 as by a screw 33 threaded into thesupport 3|. Each screw 33 also secures a terminal 34 to the bottom ofthe base 2! accessible for connection to an external circuit.

Disposed to be engaged by each of the mobile contacts 2| are spacedfixed stops or contacts 36 and 31, which may form an upper contact and alower contact. The upper contacts 36 are formed by spaced elongatedrigid metallic strips, each strip being mounted in a cantilever fashionon a shoulder 38 spaced above the shoulder 32. The free end of eachstrip overlies a mobile contact 2i and is engageable thereby when themovable contacts are in their upper position as shown in Fig. 8. Eachstrip is secured to its respective shoulder 38 by a rivet 39 extendingthrough the strip, the base 21 and a terminal 4i, mounted on the bottomof the base 21, to be accessible for connection to an external circuit.The lower contacts 31 are formed by metallic elements each having a pad42 and a free end 43 offset with respect to the pad and disposeddirectly below and in spaced relation with one of the strips forming thecontacts 36. Each free end 43 is disposed to be engaged by one of themobile contacts 2| when the latter are in their lower position as shownin Fig. 2. Each lower contact is secured to the base 27 as by a rivet 44extending through the pad 42, the base 21 and terminal 45 mounted on thebase and accessible from the exterior of the housing for connection toan external circuit. A rib 4'! formed on the bottom of the housingseparates the terminals 4|, 34 and 45 adjacent one side of the housingfrom the terminals 4|, 34 and 46 (not shown) adjacent the opposite sideof the housing. Where desired the strips, forming the contacts 36, andthe elements, forming the contacts 37, may be provided with inlaidcontact surfaces to insure a good electrical contact between the mobilecontact 2| and the contacts 36 and 3?. A partition 48 extending from oneend of the chamber 24 to a central portion thereof separates thecontacts 35, 2| and 31 adjacent one side of the chamber from thecontacts 35, 2| and 31 adjacent the opposite side of the chamber 24 soas to prevent arcing r flashing therebetween.

The double snap acting spring system 22 is disposed adjacent the freeends of the leaf springs 29 and is interconnected with each leaf spring29 to move the mobile contacts 2| between the contacts 36 and 31 with asnap action. In this en.- bodiment of the invention the spring systemincludes a bracket an anchor 52, an actuator 53, a coil spring 54, atoggle link 56 and a driver 51. The anchor 52 includes spaced upstandingsides 58 (see Fig. 9) and a pad 59 on the base 21. The bracket 5|includes an upstanding portion 8| and a pad 62. The pad 62 rests on thepad 59 and the upstanding portion 5| is spaced from the side portions58. A rivet 63 extending through the pads 82 and 59 and the base 21secures the anchor 52 and bracket 5| to a shoulder 54 formed near theend of the chamber opposite to the shoulders 38.

The actuator 53, best shown in Figs. 2, 3 and 4, is pivotally supportedon the bracket 5|, the upstanding portion Bl of which has upwardlyprojecting ears 66 adjacent the edges for the reception of the actuatortherebetween. The upper ends of the ears are provided with 1nwardlyextending lugs 51 adapted to overhang the actuator and retain the samein place. One

.end of the actuator is shaped to cooperate with the ears 6B inpivotally supporting the actuator and has a portion 68 snugly but freelyreceived between the ears 55 below the lug 5? and provided withlaterally disposed tabs 69 shaped to bear against one side of the ears65 as best shown in Figs. 2 and 3. The pivotal connection between theactuator and the bracket 5| is referred to hereinafter generally by thenumeral N. This construction maintains the parts in assembled positionand prevents movement of the actuator 53 transversely of the bracket 5|.The end of the actuator 53 spaced from the bracket 5| s bent back uponitself and shaped to form a pro ection 12 shaped to pivotally engage arecessed end cap 13 on one end of the coil spring 54. The p votalconnection between the cap and the projection is referred to generallyby the numeral 14.

The rigid toggle link 56 as best seen 1n F1g 3 is generally U-shaped andcomprises a br dg ng portion 16 and spaced legs 11. The bridging of thebracket portion 15 extends through an aperture 19 in the bracket 5| andis movable between opposed positions or stops defined by the upper sidewall 8| defining the aperture and the head 82 of the rivet 53 whichsecures the pad 52 on the base. A projection 83 is formed on thebridging portion between the legs T! to pivotally support the cap 84 onthe opposite end of the coil spring 54, the pivotal connection beingdesignated generally by the numeral 38. The legs 7'! of the toggle linkare spaced to permit movement of the actuator 53 therebetween. As bestseen in Fig. 4 the outer ends of the legs 11 are offset with respect tothe bridging portion 3'5 to overlie the sides 58 of the anchor and theextreme outer ends of the legs have depending flanges 81. Each of theflanges 81 has a pivotal recess formed thereon facing the bridgingportion (5.

The driver 57 as best seen in Figs. 3 and 4 is formed as a rigid memberand includes wings 83 formed along opposite edges of the driver and anend portion 89 disposed centrally of the wings and interconnecting thelatter. One end of each wing 68 is formed with a knife edge 9! shaped tobe received in one of the recesses on the flanges 81 to define a ivotalconnection between the parts, indicated generally by the numeral 92.Tabs or shoulders 84 on each wing, disposed outwardly from the knifeedge, are disposed to engage the sides of the flanges 81 to maintain thedriver 5'; and the toggle link 55 in assembled relation. The oppositeend of each wing 88 is formed with a knife edge 98 shaped to be receivedin a recess formed on the sides 58 of the anchor 52 to define a pivotalconnection 55. Tabs or shoulders 9'! disposed outwardly from the knifeedges 90 are disposed in notches 58 formed at the upper ends of thesides 58. The above construction prevents transverse movement of thedriver with respect to the toggle link and the anchor after assembly ofthe parts and facilitates alignment of the parts during assembly of thespring. The end portion of the driver 51' terminates in an upstandingflange 99.

When the actuator 53, the toggle link 55, the coil spring 54 and thedriver 5! are mounted as shown in Fig. 2 the parts are stressed todefine a double snap acting spring system. The latter is drivinglyconnected with the leaf springs 29 through a connection as best seen inFigs. 4 and 10, the connection including an inverted T- shaped memberI62 of insulating material. The stem of the T-shaped member M2 ispivotally connected on the flange 99 as by a rivet I03 and the arms I04extend outwardly from the stem to define shoulders I66 engageable withthe bottom sides of the leaf springs 29. Pivotally mounted on the flange93 in side by side relation with the T-shaped member I62 is a member M?of insulating material having its bottom edge in substantially spacedparallel relation to the arms I M and spaced therefrom to defineshoulders I68 engageable with the top side of the leaf springs as shownin Fig. 10. The rivet H3 also pivotally supports the member Hi7 on theflange 99.

The operation of the double pole double throw switch is as follows:Assuming that the switch parts are in a position shown in Fig. 4, whichmay be considered the normal position for the switch, the shoulders i0 3then engage the top side of the leaf springs 29 and. urge the mobilecontacts 2| into engagement with the lower fixed contacts 37. The springsystem is biased so that the mobile contacts 2| are urged intoengagement with the contacts 37 with a positive pressure.

The pivotal connection between the flange 99 and the member I02 insuresthat the pressure between each mobile contact 2| and its associatedfixed contact 31 is approximately uniform. When the plunger 23 isdepressed the actuator 53 is moved about the pivotal connections H andthe pivotal connection 14 is moved through a plane definedby the pivotalconnection 92 and the pivotal connection 86. The position of the partswith respect to each other just prior to movement of the pivotalconnection 14 through the above described plane is shown in Fig. 6. Assoon as the pivotal connection 14 passes through the above describedplane the bridging portion 15 of the toggle 56 is caused to move betweenthe stops 6| and 82 with a snap action. As the bridging portion 16 movesbetween the stops it moves the pivotal connection 86 through a planedefined by the pivotal connection 92 and the pivotal connection 96. Assoon as the pivotal connection 86 passes through this plane the free endof the driver 51 is moved between its opposed positions with a snapaction. Thus the snap movement of the bridging portion 16 between thestops 0I and 82 effects snap movement of the free end of the driverbetween opposed positions. When the free end of the driver moves betweenits opposed positions the shoulders I08 are moved out of engagement withthe top side of the leaf springs 29 and the shoulders I06 are movedrelative to the leaf springs 29 and engage the latter. Until movement ofthe driver 51 occurs, positive pressure is applied by the shoulders I08on the leaf springs 20 so that the mobile contacts 2| are urged intoengagement with the contacts 31. As soon as the shoulders I06 start tomove the resiliency of the springs 29 also causes the contacts 2| tomove away from the contacts 31. This resiliency of the leaf springs 29and the force applied by the driving spring system effects the breakingof welds in the event such should form between the contacts 2| and 31.movement of the driver 51 the snap spring system is stressed so that theshoulders I06 engage the bottom sides of the leaf springs 29 and urgethe mobile contacts 2| into engagement with the contacts 36 with apositive pressure. The pivotal'mounting of the inverted T-shaped memberI02 insures that the pressure between each mobile contact 2I and itsassociated fixed contact 36 is substantially uniform. It is to beunderstood that Where desired the shoulders I06 and the shoulders I68may be in closely spaced relation so as to engage the leaf springs 29 inboth positions of the latter. In this instance there would be no lostmotion between the shoulders on the leaf springs as is the case for theconstruction described hereinbefore.

When the force on the plunger 23 is released the pivotal connection 14passes through a plane defined by the pivotal connections 86 and thepivotal connection 92. When this occurs the bridging portion 15 of thetoggle moves between the stops BI and 82 with a snap movement. As thebridging portion 16 moves between the stops, the toggle member carriesthe pivotal connection 86 through a plane defined by the pivotalconnections 92 and 96 and as a result the free end of the driver ismoved between its opposed positions with a snap motion. At it moves theshoulders I06 are moved out of engagement with the leaf springs 29 andthe shoulders I06 move into engagement therewith. During this move mentof the shoulders, the springs 29 are urged At the conclusion of the 6.away from the contact 36 due to the resiliency of the springs. At theconclusion of the snap movement of the driving member 51 the mobilecontacts 2I are forced into engagement with the contacts 31 as describedhereinbefore. The opposed positions of the driver described herein aredetermined by engagement of the mobile contacts 2| with the contacts 36and 31 respectively. -The above construction is extremely simple, andthe parts may be formed as metal stampings. Also the parts are of suchshape and configuration that they can be readily assembled. The size andshape of the spring system is such that it can be disposed in a housinghaving the same as the dimensions as a standard snap action precisionswitch. This construction provides for uniform contact pressure,breaking of welds and the maintenance of positive pressure on thecontacts until snap action of the movable contacts occurs. Thisconstruction also minimizes the tendency of the switch contacts tobounce upon moving into engagement with the fixed contacts.

I claim: 1. In a snap acting-device, the combination of a base, aplurality of pairs of spaced stops mounted on said base, a pair offlexible leaf springs, each spring having an end free to move betweenone of said pairs of stops, means on said base for supporting theopposite end of each leaf spring to provide a cantilever mountingtherefor, a double snap acting spring system mounted on said baseadjacent the free ends of said leaf springs, said double snap actingspring system comprising two snap mechanisms operatively interconnectedso that the snap action of the first snap mechanism effects a successivesnap action operation of the second snap mechanism between opposedpositions a driving connection between said second snap mechanism of thedouble snap acting spring system and the free ends of each of said leafsprings for moving said free ends simultaneously between said stops,said double snap acting spring system in each position of said secondsnap mechanism being stressed to urge said leaf springs into engagementwith their respective stops with a positive pressure until the instantof movement of said second snap mechanism of the double snap actingspring system between its opposed positions, and means for actuatingsaid first snap mechanism of the double snap spring system to effectmovement of said free ends of the leaf springs between said stops.

" 2. In a snap acting device, the combination of a base, a plurality ofsets of spaced stops mounted on said base, a cantilever mounted contactcarrier'movable between each pair of said sets of stops and biased to beout of engagement with either adjacent spaced stop, a double snap actingspring system mounted on said base in end to end relation with saidcontact carriers, said double snap acting spring system comprising twosnap mechanisms operatively interconnected so that the snap action ofthe first snap mechanism effects a successive snap action operation ofthe second snap mechanism between opposed positions, a lost motiondriving connection between said second snap mechanism of the double snapacting spring system and the free end of each of said contact carriersincluding a pair of spaced shoulders engageable with each of.sai'd'contact carriers, said double snap acting spring system in eachposition of said second snap mechanism being stressed to urge oneshoulder of each pair into engagement with its respective contactcarrier to force the latter into engagement with one of its associatedstops with a positive pressure until the instant of movement of saidsecond snap mechanism of the double snap acting spring sys-- tem betweenits opposed positions and upon limited relative movement of said secondsnap mechanism of the double snap acting spring system, said othershoulder of each pair being engageable with the associated contactcarrier, and means for actuating said first snap mechanism of the doublesnap spring system to effect simultaneous movement of said contactcarriers between said stops.

3. In a double pole double throw switch, the combination of a base, aplurality of pairs of opposed contacts mounted on said base, a pair ofelongated flexible contact carriers mounted in side by side coplanarrelation and each having an end portion movable between one of saidpairs of opposed contacts, a mobile contact mounted on each of said endportions, means for mounting the opposite ends of theicontact carrierson said base in cantilever fashion, said contact carriers being biasedto urge the mobile contacts out of engagement with the respectiveopposed contacts, a double snap acting spring system mounted on saidbase adjacent the movable end portions of said contact carriers, saiddouble snap acting spring system comprising two snap mechanismsoperatively interconnected so that the snap action of the first snapmechanism effects a successive snap action operation of the second snapmechanism, a member connected to said second snap mechanism of thedouble snap acting spring system and movable between opposed positionswith a snap action upon said snap action of the second snap mechanism ofthe double snap acting spring system, pairs of pivotally mounted spacedshoulders on said movable member engageable with the movable end portionof each contact carrier, said double snap acting spring system beingstressed to have a shoulder of each pair engageable with one of saidcontact carriers in each position of the member to urge the associatedmovable contact into engagement with opposed contact with a positivepressure until movement of the movable member occurs, and means foractuating said first snap mechanism of the double snap acting springsystem to effect movement of said member.

4. In a double pole double throw switch, the combination of a, base, aplurality of pairs of opposed contacts mounted on said base, a pair ofelongated flexible contact carriers mounted in side by side coplanarrelation and each having an end portion, a mobile contact mounted oneach end portion and movable between one of said pairs of opposedcontacts, said contact carriers being biased to urge each mobile contactout of engagement with either of the adjacent opposed contacts, meansfor mounting the opposite ends of the contact carriers on said base incantilever fashion, a double snap acting spring system mounted on saidbase adjacent the end portion of said contact carrier, said double snapacting spring system comprising two snap mechanisms operativelyinterconnected so that the snap action of the first snapmechanismefiects a successive snap action operation of the second snapmechanism, a member connected to said second snap mechanism of thedouble snap acting spring system and movable between opposed positionswith a snap action upon said snap action of the second snap mechanism ofthe double snap acting spring system, pivotally mounted spaced shoulderson said movable member engageable with the end portion of each contactcarrier, said double snap acting spring system in each position of saidmember being stressed to urge said movable contacts into engagement withthe opposed contacts with a positive pressure until movement of themovable member occurs, said pivotally mounted shoulders providing foruniform pressure between the mobile contacts and the opposed contacts ineach position of said member, and means for actuating said first snapmechanism of the double snap acting spring system to move said member toeffect simultaneous movement of the mobile contacts between the opposedcontacts.

5. In a snap acting device, the combination of a base, a bracket mountedon said base, an anchor mounted on said base, spaced cantilever mountedcontact carriers each having an end in spaced relation to said anchorand free to move between opposed positions, a driver pivotally supportedon the anchor and having an end portion free to move between opposedpositions with snap action, a, driving connection between said endportion and said contact carriers to move the latter, a toggle link inspaced face to face relation with said driver and having a pivotal connection with said free end portion of the driver, said toggle linkhaving a portion movable between preselected positions on opposite sidesof a first plane defined by the pivotal connection between the driverand the toggle link and the pivotal connection between the driver andthe anchor, spaced stops mounted on said base and engageable with saidtoggle link to limit movement of said portion between said preselectedpositions, resilient means pivotally connected with said portion of thetoggle link and having an end free to move between opposed positions onopposite sides of a second plane defined by the pivotal connectionbetween the driver and the toggle link and the pivotal connectionbetween said portion of the toggle link and the resilient means, anactuator pivotally mounted on the bracket and pivotally connected withsaid free end of the resilient means and means engageable with theactuator for moving it to move said pivotal connection between theactuator and the resilient means through the second plane to move saidportion of the toggle link through the first plane to effectsimultaneous movement of the free ends of said contact carriers betweensaid opposed positions.

6. In a snap acting device, the combination of a support, a bracketmounted on said support, an anchor mounted on said support, spacedcoplanar contact carriers, means for mounting each contact carrier tohave an end in spaced relation to the anchor and free to move betweenopposed positions, a driver supported on the anchor and having an endportion extending away from said anchor, said end portion being free tomove between opposed positions with a snap action and interconnectedwith said contact carriers to move the latter, a toggle link in spacedface to face relation with said driver and interconnected with said freeend portion of the driver, said toggle link having a movable end, acompression spring interconnected with the free end of the toggle link,stop means engage... able with said toggle link to limit movement of thepivotal connection between the toggle and the compression spring betweenpositions on opposite sides of a plane defined by the pivotal connectionbetween the driver and the toggle link and the pivotal connectionbetween the driver and the anchor, an actuator supported on said bracketand interconnected with the compression spring and free to move thepivotal connection between the actuator and the compression springbetween positions on opposite sides of a plane defined by the pivotalconnection between the driver and the toggle link and the pivotalconnection between the toggle link and the compression spring and meansengageable with the actuator for moving it to move the pivotalconnection between said actuator and the compression spring through thesecond plane to move the pivotal connection between the compressionspring and the toggle through the first plane to eifect simultaneousmovement of the free ends of said contact carriers between said opposedpositions with a snap action.

'7. In a snap acting device, the combination of a base, a bracketmounted on said base, an anchor mounted on the base, a driver pivotallysupported on the anchor and having an end portion free to move betweenopposed positions with snap action, a toggle link in side by siderelation with said driver, said toggle link being pivotally connectedwith said free end portion of the driver and having a movable end, acompression spring pivotally connected with the free end of the togglelink and having a movable end, means engageable with the toggle link forlimiting movement of the pivotal connection between the toggle link andthe compression spring between positions on opposite sides of a firstplane defined by the pivotal connection between the driver and thetoggle link and the pivotal connection between the driver and theanchor, an actuator in side by side relation with the toggle link andpivotally supported on the bracket, said actuator having an endpivotally connected with said movable end of the compression spring andfree to move the pivotal connection between the actuator and thecompression spring between positions on opposite sides of a second planedefined by the pivotal connection between the driver and the toggle linkand the pivotal connection between the toggle link and the compressionspring and means engageable with the actuator for moving it to move thepivotal connection between the actuator and the compression springthrough the second plane to move the pivotal connection, between thecompression spring and the toggle link through the first plane to efiectmovement of the free end portion of the driver between said opposedpositions.

8. In a multi pole double throw switch, the combination of a support, aplurality of pairs of spaced contacts mounted on said support, spacedresilient leaf springs each carrying a movable contact, means formounting each spring with said movable contact-associated therewith freeto move between one of said pairs of spaced contacts, an anchor mountedon the support and spaced from said spaced contacts, a bracket mountedon said support, a driver pivotally mounted on the anchor and having anend portion adjacent said spaced contacts and free to move betweenopposed positions with a snap action, a lost motion driving connectionbetween said ,free end portion and each of said leaf springs, a togglelink in side by side relation with said driver and pivotally connectedwith said free end portion of thedriver, said toggle link having aportion movable between opposed positions on opposite sides of a firstplane deand the pivotal connection between said portion of the togglelink and the compression spring, an actuator pivotally mounted-Yon thebracket and having an end pivotally connected with said free end of thecompression spring and means engageable with said actuator for moving itto move said free end of the compression spring across the second planetov move said portion of the toggle link across the first plane toeiTect a snap movement of said movable contacts between said spacedcont-acts through said connection.

9. In asnap acting device, the combination of a base, spaced stop meansmounted on saidv base, a rigid upstanding bracket mounted on said base,a rigid anchor'disposed between said" stop meansand the bracket, a rigiddriver pivotally mounted on said anchor and having an endfree to move,means. acting between said stop means and said free end for limitingmovement thereof between opposed positions, a rigid toggle I link inside by side relation with said driver and having a pivotal connectionwith said free end of the driver, said toggle link having a movable end,'a resilient coil spring having a pivotal con-- nection with the freeend of the toggle link and having a movable end, spaced stop meansengageable with said toggle link to limit movement of the pivotalconnection between the toggle link and the coil spring between positionson opposite sides of the first plane defined by the pivotal connectionbetween the driver and the toggle link and the pivotal connectionbetween the, driver and the anchor, a rigid actuator pivotally supportedon said bracket and pivotally connected with the movable end of the coilspring and free to move the pivotal connection between the actuator andthe coil spring'between positions on opposite sides of asecond planedefined by the pivotal connection between the driver and the toggle linkand the pivotal connection between the toggle link and the coil springand means engageable with said actuator to move the pivotal connectionbetween the ac-v tuator and the coil spring through the second plane toefiect movement of the pivotal connection between the toggle'link andthe coil spring through the first plane to effect movement of the freeend of the driver between said opposed positions with a snap action,said driver in either of its opposed positions applying a positivepressure on said stop means until snap movement occurs.

10. In a snap acting device, the combination of a support, a bracketmounted on said support, an anchor mounted on said support, a driverpivotally supported on the anchor and having an end portion free to movebetween 0p-. posed positions with snap action, means acting between saidanchor and said driver forholding the latter against movementtransversely of the anchor, a toggle link in side by side relation withsaid driver, said toggle link being pivotally connected with said endportion of the driver-and having a movable end, resilient meanspivotallyconnection between the driver and the toggle link and the pivotalconnection between the driver and the anchor, means acting between saidtoggle link and said driver for preventing. movement of said toggle linktransversely of the driver, an actuator pivotally supported on saidbracket and pivotally connected with said movable end of the resilientmeans and free to move the pivotal connection between the actuator andthe resilient means between positions. on op.-. posite. sides of asecond plane. defined by the pivotal connection between the driver; andthe toggle link and the pivotal connection between the toggle link andthe resilient means, means. acting between the actuator and. the brackettor holding the actuator against movement trans versely of. the bracketand means engageable with said actuator for moving it to move the.pivotal connection between the'actuator and the resilient. means throughthe second: plane to. move the pivotal connection between the. re.-.silient means and. the toggle link through the first plane to effectsnap. movement. of the end portion of said driver between said opposedpositions.

1,1. In a snap. acting device, the combination of a support, anupstanding bracket having an. aperture, an anchor having spaced. pivotalrecesses facing. away from said bracket, a. driver having an end-portionfree tomove between. op.- posed positions and having spaced wingsinterconnectedwith said end porti'o'n' and defining the sides of saiddriver, each of saidwings having a knife edge shaped to be received inone of said pivotal, recesses on saidanchor and having. a knife edgefacing away from said anchor, means acting between each. wing and-theanchor for maintain.- ing said driverin assembled relation with. theanchor, a. toggle link comprising. agenerall'y. U- shap'edamember havingspaced legsand a' bridging. portion, each of said legs having a recessshaped to receive: the knife edge on the wings facing away from, theanchor, sai'd' movable bridging portion shaped to be receivedin' saidaperture, a compression spring pivotally. connected with said. bridgingportion and ha-ving a movable. end,- stops, one of'which is defined byone of: the side. walls of. the aperture, positioned to; beengageable bysaid bridging portion to limit movement of the pivotal connectionbetween thebri'dging portion and the compression. spring betweenposition's on opposit sides of a first plane definedby the. pivotalconnectionbetweenthe driver andthe legs and the pivotal support. betweenthe driver. and the anchor,. means acting between each wing andiitsassociated leg for-holding-..said toggle link and said driver inassembled relation, an actuator pivotally' mounted. on. said bracket andhaving an end shaped to. pass between thelegs ofsaidtoggle linkand to bepivotally. connected with saidimovable endi-of'the' compression springand free to move. said pivotal connection between said actuator andthe-compression spring between positions on opposite sides of a secondplane defined by the pivotal connection between the driver and the legsand the pivotaliconnection between thebridging portionandLthecompression.

spring, means acting 4 between saidflbracket. and opposite sides of theactuator to maintain-the actuator in assembled relation and means en:gageable with said actuator to move said pivotal connection between theactuator and the compression spring through the second plane to move thepivotal connection between the compression spring and the bridgingportion through the first plane to efiect movement of the; free endportion of the driver between said opposed positions.

12. In a snap acting device, the combination of a base, an upstandingbracket having an aperture and spaced sides on opposite sides of thebracket, said sides each having aninwardly facing recess; an anchorhaving spaced upstanding sides each having an outwardly facing notch atthe extreme upper end ofthe side and a recess facing in a direction awayfrom the bracket; a driver having an end free tomove-between opposedpositions with a snap action and having wings interconnected with saidend portion disposed onopposite sides thereof; one end of each winghaving a knife edge shaped to be received in the recesson said sides ofthe anchor and having ashoulder portion shaped to be received insaidnotch, the opposite end; ofeach of said wings being; formed wi-thaknife edge facingaway from said anchor, a toggle link comprising agenerally U- shaped member having spacedlegs and a bridging portion,eachof said legs having its outer end formed with a flange, each ofsaid'flangeshavinga recess shaped to receiveone of the knife edges onsaid Wings facing awayfromthe anchor, said bridging portion being shapedto be received in said aperture and having a projection extendingbetween said legs, a compression spring having an endpivot-al-l'vmountedon saidprojection and; having its opposite enddisposed between said legs and free to move, spaced stops, one of whichis formed, by aside wall of said aperture; en gageable with saidbridging portion to limit movement of the pivotal connection between thetoggle link and the compression spring between positions. on oppositesides of a first" plane defined by the knife edgeson the wings, anactuator having anendformed, with sides shapedft be received in saidrecesses onthe bracket andjhav- 111g ho lde n a a l t h b a ket.maintain the actuator in assembled relationwith e k t. a ect ie rhav nts nq iie. end. shaped to pass betweenthe legs of the-to gle linkand-having a projection shaped to be pivotally connectedwith themovable: end of the compres' sion spring and; free, to move thepivotalconnec-. tion between the: actuator the compression spring-on oppositesifld es;o f a second plane defined, by the knife edges on said wingsfacing away from theanchor and" the pivotalconnection be tweenthecompression spring and the toggle link, and a plunger engageable. withsaid actuator to move saidpivotal-connection between the actu ator andthe compression spring through said? second plane to move the pivotalconnection be tween se link ha empr ions ri through; the first' plane toeffect successive snap} movements of the bridging: portion of the togglelink and the; free end portion ofthe driver,

13% In a spa-p acting device; in combination, a base, apairof'spacedstops fixedly mounted on said-base, acontact carrier-movable betweensaid stops, a- -doubiesnap acting spring system comprising two snapmechanisms operatively interconnected sothat the snap actionof the firstsnaptmechanism effects a successive-snap-actienoperation. of the secondsnap mechanismbe tween. spacedpcsitions, a-lost-motion driving con--nectiombetween; saidcisecond :snan-.mecl1anism ct the double snap actingspring system and the contact carrier for moving said contact carrierbetween the spaced stops with a snap action, said double snap actingspring system in each of the spaced positions of said second snapmechanism thereof being stressed to exert a'positive pressure againstthe contact carrier to urge the. same into.

engagement with the respective stop until :the instant of movement ofsaid second snap mechanism of thedouble snap acting spring systembetween its positions, and means foractuating said first snap mechanismof the double snap acting spring system to effect movement of thecontact carrier between said stops.

14. In a snap acting device, in combination, a base, a pair of spacedstops fixedly mounted on said base, a contact carrier movable betweensaid stops and biased to be out of engagement with either of said stops,a double snap acting spring system comprising two snap mechanismsoperatively interconnected so that the snap action ofthe first snapmechanism effects a successive snap action operation of the second snapmechanism between spaced positions, a driving connection between saidsecond snap mechanism of the double snap acting -spring system and thecontact carrier for moving said contact,

carrier between the spaced stops with a snap action, said double snapacting spring system in each of the spaced positions of said second snapmechanism thereof being stressed to exert a positive pressure againstthe contact carrier to urge the same into engagement with the respectivestop until the instant of movement of said second snap mechanism of thedouble snap acting spring system between its positions, and means foractuating said first snap mechanism of the double snap acting springsystem to effect movement of the contact carrier between said stops.

15. In a snap acting device, in combination, a base, a pair of opposedspaced stops fixedly mounted on said base, a contact carrier movablebetween said stops and resiliently biased to be out of engagement witheither of said stops, a double snap acting spring system mounted on saidbase, said double snap acting spring system comprising two snapmechanisms operatively interconnected so that the snap action of thefirst snap mechanism effects a successive snap action operation of thesecond snap mechanism between opposed spaced positions, a drivingconnection between said second snap mechanism of the double snap actingspring system and the contact carrier for effecting movement of saidcontact carrier between the spaced stops with a snap action, said doublesnap acting spring system in each of the opposed positions of saidsecond snap mechanism thereof being stressed to exert a positivepressure against the contact carrier to urge the same into engagementwith the respective stop until the instant of movement of said secondsnap mechanism of the double snap acting spring system from one of itsopposed positions to the other, and means for actuating said first snapmechanism of the double snap acting spring system to effect movement ofsaid second snap mechanism of the double snap acting spring systembetween its opposed positions to thereby move the contact carrier fromone of the opposed fixed stops to the other.

16. In a snap acting device, in combination, a base, a pair of opposedspaced stops fixedly mounted on said base, a flexible leaf spring havingan end free to move between said stops, means on said base supportingthe other end of said leaf spring to provide a cantilever mountingtherefor, a double snap acting spring system mounted on said base, saiddouble snap acting spring system comprising two snap mechanismsoperatively interconnected so that the snap action of the first snapmechanism effects a successive snap action operation ofthe second snapmechanism between opposed positions, a driving connection between saidsecond snap mechanism of the double snap acting spring system and thefree end of the leaf spring for moving said free end between the opposedstops with a snap action, said double snap acting spring system in eachposition of said second snap mechanism thereof being stressed to exert apositive pressure to urge the leaf spring into engagement with therespective stop until the instant of movement of said second snapmechanism of the double snap acting spring system between its opposedpositions, and means for actuating said first snap mechanism of thedouble snap acting spring sys-.

tem to effect movement of the free end of the leaf spring between saidstops.

i 17. In a snap acting device, in combination, a base, a pair of opposedspaced stops fixedly mounted on said base, a flexible resilient leafspring having an end free to move between said stops, means on said basesupporting the other end of saidleaf spring to provide a' cantilevermounting therefor, said leaf spring being biased to urge its free endaway from engagement with either of the opposed stops, a double snapacting spring-system mounted on said base, said double snap actingspring system comprising two snap mechanisms operatively interconnectedso that the snap action of the first snap mechanism effects a successivesnap action operation of the second snap mechanism between opposedpositions, a driving connection between said second snap mechanism ofthe double snap acting spring system and the free end of the leaf springfor moving said free end between the opposed stops with a snap action,said double acting snap spring system in each position of said secondsnap mechanism thereof being stressed to exert a positive pressure tourge the leaf spring into engagement with the respective stop until theinstant of movement of said second snap mechanism between its opposedpositions, and means for actuating said first snap mechanism of thedouble snap acting spring system to effect movement of the free end ofthe leaf spring between said stops.

18. In a snap acting device, in combination, a base, a pair of opposedspaced contacts fixedly mounted on said base, a cantilever mounted leafspring mounted on said base and having an end free to move between saidopposed fixed contacts, a mobile contact mounted on said leaf springadjacent the free end thereof to be movable for alternate engagementwith one or the other of said fixed contacts, said leaf spring beingbiased to urge the mobile contact out of engagement with either of theopposed fixed contacts, a double snap acting spring system mounted onsaid base, said double snap acting spring system comprising two snapmechanisms operatively interconnected so that the snap action of thefirst snap mechanism effects a successive snap action operation of thesecond snap mechanism movable between opposed positions, a drivingconnection between said second snap mechanism of the double snap actingspring system and the gamma free endof the leaf spring for movingthemobile contact between the opposed fixed contacts with a snap action,said double snap acting spring system in either position of said secondsnap mechanism thereof being stressed to exert a positive pressureagainst the freeend of the leaf spring to urge the mobile contact intoengagement with the respective fixed contact until the instant ofmovement of said second snap mecha nism of the double snap acting springsystem to its other position, and means for actuating said first snapmechanism of the double snapacting spring system to effect movement ofsaid secand snap mechanism of the double snap actingspring systembetween its opposed positions to thereby move the contact carrier fromengagement with one of the fixed contacts into engagement with the otherfixed contact.

19. In a snap acting device, in combination, a base, a pair of opposedspaced contacts fixedly mounted on said base, a cantilever leaf springmounted at one end on said base and having its other end free to movebetween said fixed contacts, a mobile contact mounted on said leafspring adjacent the. free end thereof to be movable for alternateengagement with one or the other of said fixed contacts, said cantileverleaf spring being biased to urge the mobile contactout of engagementwith either 01' the fixedcontacts, a double snap acting. springsystemmounted on said base comprising two snap: mechanisms operativelyinterconnected so that the snap action of the first. snap mechanismeffects a suecessive snap action operation of the second snap mechanism,said second snap mechanism of the 16 double snap acting spring systemhaving an end adjacent the tree end of the cantilever leaf spring freeto"- move between opposed positions with a snap action, a memberpivotally mounted on said end at said second snap mechanism of thedouble snap actmg spring system for movement between said opposedpositions and engageable with the free end of the cantilever leaf springfor moving the mobile contact between the opposed fixed contacts with asnap action, said double snap acting spring system in either opposedposition of said movable member being stressed to exert a positivepressure against the free end of the cantilever leaf spring to urge themobile contact into engagement with the respective fixed contact untilthe instant of movementof said movable member to its other opposedposition, and means for actuating said first snap mechanism of thedouble snap acting spring system to effect movement of the mobilecontact between said fixed contacts.

VVILBERT A. MARTIN.

References Cited in the file of this patent UNITED STATES PATENTS

